Cutting head assembly



E. G. MOGOVERN CUTTING HEAD ASSEMBLY Aug. 10, 1954 s Sheets-Sheet 1 Filed Dec. 17, 1955 Edward GDMcGoI/ern INVENTOR.

Aug. 10, 1954 E. G. MQGOVERN "CUTTING HEAD ASSEMBLY 3 Sheets-Sheet 2 Filed Dec. 17, 1953 Wm Mm 111 F6 Nv Edward 6. MCGo vern INVENTOR.

Aug. 10, 1954 5 G. M GOVERN 2,685,766

CUTTING HEAD ASSEMBLY Filed Dec. 17, 1955 3 Sheets-Sheet 3 a 4 Fig.4

Fig. 7

Edward 61 McGovern JNVENTOR.

Patented Aug. 10, 1954 UNITED STATES ATENT OFFICE 11 Claims.

This invention relates in general to improvements in metal working tools, and more specifically to an improved cutting head assembly for a cut-off grinder.

It is to be understood that under given conditions, a certain grinding wheel will out only at a certain effective rate. Any attempt to vary the conditions under which the grinding wheel operates will reduce its effectiveness. Therefore, a cutting head assembly is generally limited in production by the effective rate of cutting of the grinding Wheel carried thereby.

The primary object of this invention is to provide an improved cutting head assembly which is so constructed whereby the cutting rate thereof may be substantially double that of conventional cutting head assemblies.

Another object of this invention is to provide an improved cutting head assembly which utilizes a pair of grinding Wheels, the grinding wheels being mounted to operate sequentially on metal being cut or ground with the grinding wheels operating at different depths.

A further object of this invention is to provide an improved cutting head assembly for reciprocating grinders, the cutting head assembly including a pair of aligned grinding wheels with the grinding Wheels being set to grind at diiferent depths so that a pair of cuts may be made in a single traversing of the cutting head assembly.

A still further object of this invention is to provide an improved cutting head assembly which includes means for mounting a pair of grinding wheels for operation in unison, the means being adapted to position the grinding wheels so that they have different effective depths of cuts and being so constructed whereby the relationships of the wheels shift at the end of each effective stroke of the cutting head assembly.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a top plan view of a reciprocating grinder utilizing the cutting head assembly which is the subject of this invention, a support for material to be worked on being omitted;

Figure 2 is a fragmentary front elevational view of the reciprocating grinder of Figure 1 and shows the general relationship of the cutting head assembly with respect to a supporting trackway;

Figure 3 is an enlarged rear perspective view of the cutting head assembly and shows the general details thereof, a hood portion thereof being omitted for purposes of clarity;

Figure 4 is an enlarged fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 4-- l of Figure l and shows the general relationship of the grinding wheels with respect to the supporting carriage therefor;

Figure 5 is an enlarged fragmentary bottom plan view of the cutting head assembly and showing the relationship of the grinding wheels and the means for driving the same;

Figure 6 is an enlarged fragmentary transverse vertical sectional view taken substantially upon the plane indicated by the section line 66 of Figure 4 and shows the manner in which a support arm for the grinding wheels is rockingly carried by a support for limited movement; and

Figure 7 is an enlarged fragmentary perspective view of the lower end of the support and shows the relationship between the support and the support arm rockingly carried thereby, and the means for limiting rocking movement of the support arm, means for rocking the support arm relative to the support being omitted for purposes of clarity.

Referring now to the drawings in detail, it will be seen that there is illustrated in Figures 1 and 2 a reciprocating grinder utilizing the cutting head assembly which is the subject of this invention. The reciprocating grinder includes an elongated platform 19 which extends transversely of a work carrying platform (not shown) and is mounted for vertical movement on a pair of plungers I2. The plungers i2 are parts of vertically extending fluid cylinders l4 whose operations are controlled by electrically controlled valve means (not shown).

The cutting head assembly, which is the subject of this invention, is referred to in general by the reference numeral i6 and include a carriage which is referred to in general by th reference numeral E8. The carriage I8 is formed of a platform 29 and supporting rollers 22. The supporting rollers 22 are guidingly engaged with rail 24 mounted on the platform It in spaced parallel relation. Secured to the platform 2a is a plunger 25 of a horizontally disposed fluid cylinder 28. The fluid cylinder 23 is provided with a control valve (not shown) which is remotely electrically controlled.

Carried adjacent each of the fluid cylinders M in offset relation with respect to the platform ill is a standard 39. The standard as has mounted on the upper end thereof a limit control switch 32. Each limit control switch is alzernatingly engaged by a lever 3 5. There are two such levers 34, with each lever 34 being disposed adjacent an end of an elongated shaft 35 which is rigidly secured to the platform 253 by mounting arms It will be understood that the levers 34 are adjust-ably mounted on t -e shaft 36 to vary the relationship of the carriage it with respect to the platform it when the limit switches 32 are tripped.

It to be understood that the above mentioned parts are portions of a conventional reciprocating grinder, and their relationship need not be set forth in more detail herein. t is also to be understood that normally a single grinding wheel is carried by the platform of the carriage l8 and it is to be driven. In operation, the carriage i8 is reciprocated back and forth along the tracks 26 due to the actuation of the hydraulic cylinder 28. As the carriage it reaches the end of one or its strokes, one of the levers 3 will trip the limit switch 32 with which it co operates. The tripping of the limit switch will result in the reversal of flow of fluid in the cylinder as to reverse the movement of carriage l8. Simultaneously, fluid will be permitted to escape from the cylinders i l so as to permit the lowering of the carriage i8 and its associated grinding wheel a predetermined amount so that the grinding wheel may be lowered into position for a next out.

It will be noted that the platform It is provided with an elongated opening 46 between the rails 24. The opening til has received therein an intermediate portion of an elongated. support i2 carried in depending relation by the underside of the platform 2i? of the carriage 8. The support 42 is bifurcated at its lower end, best illustrated in Figure 7, and includes a pair of depending flanges 44 which are inwardly offset. Passing between the flanges ts and supported for rocking movement is a support arm it.

Referring now to Figure 6 in particular, it will be seen that the support arm :5 is mounted for rocking movement relative to the support as on a shaft as which extends transversely of the support arm it. The shaft 43 includes a generally rectangular cross-sectional central portion which is rigidly keyed to the support arm it. The shaft also includes circular cross-sectional end portions which are suitably journaled in the flanges as. The end portions 52 are provided with keyways in which are seated keys E l. The keys 5:4 retain collars 56 on the shaft it.

It will be noted that each of the collars be is provided at its top with a notch 58. Received in the notch 58 of each collar is a depending key stone-shaped lug til carried by the support it and disposed outwardly of an adjacent flange M. It will be understood that the relationship between the lug 6i? and the notch 5a is such so as to limit the rocking movement of the support arm 46 with respect to the support 42.

Carried by the support arm it adjacent op posite ends thereof and extending transversely of the support arm from opposite faces thereof are tubular shaft housings 62. Mounted each of the shaft housings 52 and extending through the support arm as is a rotatable shaft 5d. Car'- ried by one of each rotatable shaft 64 is a gang pulley 56. Carried by the opposite end of each shaft 54 is a grinding wheel 63, it will be noted that the gang pulleys B6 and the grinding wheels 68 are in respective alignment.

Carried by the platform 28 of the carriage l8 and pivotally connected thereto at one edge is a mounting plate iii. The mounting plate it has the opposite edge thereof supported by adjustable jack elements E2. Carried by the mounting plate its is an electric motor l t. The electric motor it has an armature shaft it on which is mounted a gang pulley til. The gang pulley i8 is in the same plane as the gang pulleys G5. Entrained over the gang pulleys to and i3 is a plurality of drive belts 8%. It will be understood that the mounting plate 10 is pivoted with respect to the platform 2% to vary the tension in the drive belts 80 so as to permit effective driving of the shaft 6 3 by the electric motor M.

Secured to the underside of the platform Zll and extending in opposite directions therefrom are water supply lines %2. The water supply lines 82 have reversely bent end portions B l which terminate in spray nozzles to directed at the grinding wheels 83. The flow of a coolant or other suitable liquid through the supply pipe 82 to the spray nozzles 86 is controlled valve 83.

Referring now to Figure l in particular, it will be seen that mounted on and supported by the supply pipes 82 is a hood 9d. The hood is secured to the supply pipes 82 through the use of suitable clips 92. It is understood that the hood 8% is to protect workmen against any flying cuttings or portions of the grinding wheels 68.

Extending transversely between portions of the hood 551 and disposed in overlying relation with respect to each spray nozzle 86 is a strap 9d. The strap Q34 has secured to the underside thereof in supporting relation a pair of shields se. The shields as are in the form of plates which converge towards an associated grinding wheel 58.

It is understood that the grinding wheels 53 he in the same plane so that when the cutting head assembly IE is reciprocated transversely of an object to be cut, the grinding wheels 63 follow in the same path. It is to be understood that if the grinding wheels 68 were disposed in the same vertical plane, that only the lead one of the grinding wheels would have a grinding action during its travel across the object being ground or cut. In order to permit the effective operation of the cutting head assembly it, it is necessary that the trailing one of the grinding wheels 653 be set for a deeper out than the lead grinding wheel. Further, inasmuch as the relationship of the grinding wheels 68 reverses at the end of each stroke of the cutting head assembly it, it is necessary that the particular relationship of the heights of the grinding wheel 6%} be reversed accordingly.

In order to retain the grinding wheels E58 in proper relation, there is carried within the lower portion of the support 42. an electromagnetic device which is referred to in general by the reference numeral use. The electromagnetic device Hill includes a pair of contacts 32 mounted on opposite sides of the support E 2. Also, the support arm 45 is provided with a pair of L-shaped contacts HM with each contact 5% being disposed adjacent a contact if. of the electromagnetic device Hill. The electromagnetic device Hill is connected to the limit switches 32 for actuation thereby. The relationship between the limit switches 32 and the electromagnetic device lilo is such that when the cutting head assembly !5 moves to the right, as viewed in Figure 4, the right contact E02 is energized to draw the associated contact W4 thereto. Thispivots the support arm 45 in acounter-clockwise direction and lowers the left hand grinding wheel 68 while the right hand grinding wheel $8 is elevated. It will be understood that the difference in the respective heights of the grinding wheels 68 is equal to the effective cut of one of the grinding wheels. Thus, as the cutting head assembly I6 is moved to the right, as viewed in Figure 4, the cutting wheel 68 disposed at the right will make an initial out across the material to be cut. Then, the left hand cutting Wheel 68 will follow in its track and make a second cut. Thus, it will be seen that the cutting head assembly i6 is of such a nature whereby twice the effective cut may be obtained through a single reciprocation of the cutting head assembly, and thereby, the efficiency of a reciprocating grinder provided with the cutting head assembly It is substantially doubled.

When the cutting head assembly [6 reaches the right end of its stroke, the associated limit switch 32 is tripped to effect movement thereof to the left. The limit switch 32 also reverses the supply of current to the electromagnetic de-' vice i with the result that the right hand contact IE2 is no longer energized, and the left hand contact :92 is energized. This causes a tilting of the support arm 46 in a clockwise direction to reverse the relationship of the two grinding wheels 68. It is to be understood that the rocking of the support arm 46 is accomplished at the end of each stroke of the cutting head assembly [6.

In view of the foregoing, it will be seen that there has been devised an extremely simple cutting head assembly, which, through the utilization of two grinding wheels which are selectively positioned during the operation of the reciprocating grinder of which the cutting head assembly is a part, will produce two cuts on material to be cut. Inasmuch as the cuts are disposed in superimposed relation, it will be seen that the effectiveness of the stroke of the cutting head assembly will be doubled. While it is realized that a slightly longer time will be required for an effective stroke of the cutting head assembly, it is to be understood that the time is not materially increased, and therefore, the production of a reciprocating grinder provided with the cutting head assembly which is the subject of this invention will be substantially doubled. It is also to be understood that although the cutting head assembly has been illustrated as being in the form of a cut-off head, it may be utilized in conventional grinding operations.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

i. A cutting head for a reciprocating cut-01f grinder comprising a carriage, a depending support carried by said carriage, a support bar carried by said support, aligned cut-off wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-off wheels may be selectively set relative to the other so that both cut-oil wheels may have effective grinding depths.

2. A cutting head for a reciprocating cut-ofi grinder comprising a carriage, a depending support carried by said carriage, a support bar carried by said support, aligned cut-off wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-01f wheels may be selectively set relative to the other so that both cut-off wheels may have eifective grinding depths, means carried by said support for selectively rocking said support arms in sequence with reversing of the direction of travel of said carriage.

3. A cutting head for a reciprocating cut-off grinding comprising a carriage, a depending support carried by said carriage, a support bar car ried by said support, aligned cut-off wheels rotatably carried by said supoprt bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-off wheels may be selectively set relative to the other so that both cut-off wheels may have effective grinding depths, means carried by said support selectively retaining said support arm in a rocked position.

4. A cutting head for a reciprocating cut-off grinder comprising a carriage, a depending support carried by said carrier, a support bar carried by said support, aligned cut-off wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-01f Wheels may be selectively set relative to the other so that both cut-off wheels may have effective grinding depths, means carried by said support for selectively rocking said support arms in sequence with reversing of the direction of travel of said carriage, said means being in the form of an electromagnetic device, cooperating contacts carried by said support arm on opposite sides of said support.

5. A cutting head for a reciprocating cut-off grinder comprising a carriage, a depending support carried by said carriage, a support bar carried by said support, aligned cut-off wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-off wheels may be selectively set relative to the other so that both cut-off wheels may have effective grinding depths, a power unit car ried by said carriage drivingly connected to said cut-off wheels.

6. A cutting head for a reciprocating cut-off grinder comprising a carriage, a depending support carried by said carriage, a support bar carried by said support, aligned cut-ofi wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cut-off wheels may be selectively set relative to the other so that both cut-off wheels may have effective grinding depths, a power unit carried by said carriage drivingly connected to said cut-off wheels, said power unit being mounted on a mounting plate, said power unit being connected to said cut-off wheels by flexible drive belts, said mounting plate being pivotally mounted for tensioning of said drive belts.

7. A cutting head for a reciprocating cut-off grinder comprising a carriage, a depending support carried by said carriage, a support bar carried by said support, aligned cut-01f wheels rotatably carried by said support bar at opposite ends thereof, said support bar being rockably mounted relative to said support whereby one of said cutoff wheels may be selectively set relative to the other so that both cut-off wheels may have effective grinding depths, cooperating means on said support and said support arm for limiting rocking of said support arm.

8. For use in combination with a carriage reciprocatingly mounted on a track and controlled by limit switches, a cutting head comprising a support adapted to be carried by the carriage, a support arm rockably carried by said support, cut-off wheels rotatably carried by said support arm at opposite ends thereof, means carried by said support selectively rocking said support arm and retaining said support arm in a rocked position, said means being operatively controlled by the limit switches.

9. For use in combination with a carriage reciprocatingly mounted on a track and controlled by limit switches, a cutting head comprising a support adapted to be carried by the carriage, a support arm rockably carried by said support, cut-off wheels rotatably carried by said support arm at opposite ends thereof, means carried by said support selectively rocking said support arm and retaining said support arm in a rocked position, said means being operatively controlled by the limit switches, cooperating means on said support and said support arm for limiting rocking of said support arm.

'10. For use in combination with a carriage reciprocatingly mounted on a track and controlled by limit switches, a cutting head comprising a support adapted to be carried by the carriage, a support arm rockably carried by said support, cut-off wheels rotatably carried by said support arm at opposite ends thereof, means carried by aid support selectively rocking said support arm and retaining said support arm in a rocked position, said means being operatively controlled by the limit switches, said means including an electromagnetic device, cooperating contacts carried by said support arm.

11. For use in combination with a carriage reciprocatingly mounted on a track and con trolled by limit switches, a cutting head comprising a support adapted to be carried by the carriage, a support arm rockably carried by said support, cut-off wheels rotatably carried by said support arm at opposite ends thereof, means carried by said support selectively rocking said sup port arm and retaining said support arm in a rocked position, said means being operatively controlled by the limit switches, said cut-off wheels being in alignment and intended to alternatingly follow in the path of each other.

No references cited. 

